PBDB Interval

International Chronostratigraphic Timescale

The interval definitions in this timescale are derived from the following sources:

K. M. Cohen, S.C. Finney, P.L. Gibbard and J.-X. Fan. 2023. The ICS International Chronostratigraphic Chart v2023/09. view
F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
W. B. Harland, R. L. Armstrong, A. V. Cox, L. E. Craig, A. G. Smith and D. G. Smith. 1990. A Geologic Time Scale 1989. view
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 view
J. Meng and M. C. McKenna. 1998. Faunal turnovers of Paleogene mammals from the Mongolian Plateau. Nature 394:364-367 view
F. M. Gradstein, F. P. Agterberg, J. G. Ogg, J. Hardenbol, P. Van Veen, J. Thierry, and Z. Huang. 1995. A Triassic, Jurassic, and Cretaceous time scale. SEPM Special Publication 54 view
J. Palfy, P. L. Smith, and J. K. Mortensen. 2000. A U-Pb and 40Ar/39Ar time scale for the Jurassic. Canadian Journal of Earth Sciences 37(6):923-944 view

There are 59 timescales which overlap this one. show

Interval boundaries marked with * have been interpolated based on the differences between the ages for international timescale boundaries quoted in the source and the currently accepted ages for those boundaries.

Interval names marked with † are no longer in current use.

This timescale is used in the definition of 127245 collections

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International Chronostratigraphic Timescale			Ordovician of the Baltic				Ordovician of China			Ordovician of Britain
Ordovician	Late Ordovician	Hirnantian	Harju	Porkuni			Hirnantian	Xiaoxita †/Shikou	Wufeng †	Ashgill	Hirnantian			443.8
		Katian		Pirgu			Chientangkiangian				Rawtheyan			445.2
											Cautleyan			448.9 *
											Pusgillian			449.3 *
							Neichianshanian/Hanjiang				Pusgillian			449.5
				Vormsi						Caradoc	Streffordian	Onnian †		449.6 *
				Nabala	Johvi †									450 *
			Viru	Rakvere										450.6 *
				Rakvere							Cheneyan			451.5 *
				Oandu							Cheneyan			452 *
				Oandu							Burrellian			452.7 *
		Sandbian		Keila	Idavere †									453
				Keila								Actonian †		453.2 *
				Haljala								Actonian †		453.9
												Marshbrookian †	Woolstonian †	454.2 *
												Longvillian †		455.2 *
				Kukruse										456.4 *
											Aurelucian			456.8 *
												Soudleyan †/Harnagian/Costonian		457.4 *
				Uhaku	Aluoja †							Soudleyan †/Harnagian/Costonian		457.5 *
	Middle Ordovician	Darriwilian		Uhaku			Darriwilian	Guniu †/Hulo		Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			458.4
				Lasnamagi										458.9 *
				Aseri										460.4 *
				Aseri							Abereiddian/Early Llanvirn			461.3 *
			Oeland	Kunda										462.9 *
					Valaste †/Hunderum									464.3 *
								Hunjiang †	Dawan †/Daobaowan/Ningkuo					466.3 *
				Volkhov		Langevoja †/Vaana/Saka								467.1 *
		Dapingian					Dapingian							467.3
										Arenig	Fennian			468.4 *
				Billingen										469.3 *
	Early Ordovician	Floian					Yiyangian							470
					Latorp †									470.1 *
											Whitlandian			471.1 *
				Hunneberg							Whitlandian			473.7 *
											Moridunian			474.3 *
		Tremadocian					Xinchangian			Tremadoc	Migneintian			477.7
									Lianghekou †		Migneintian			477.9 *
											Cressagian			480.8 *
				Varangu										481.3 *
				Pakerort										482.2 *
				Pakerort										485 *
														485.4 *
														486.3
														486.5